Analysis of protein functions has recently become important as post-genome related technology in the medical, pharmaceutical, and food industries. Particularly, in order to analyze actions of cells, it is necessary to research interactions (binding and separation) between a type of protein and another type of protein (or a low molecule compound) which are living substances in a living cell.
The interactions between a type of protein and another type of protein (or a low molecule compound) have been recently analyzed using a fluorescence resonance energy transfer (FRET) phenomenon. Interactions between molecules are herein detected within a range of several nanometers using fluorescence. Such interaction detection using the FRET phenomenon is mainly performed with a microscope system.
For example, Japanese Laid-Open Patent Application No. 2005-207823 discloses a single molecule fluorescence analysis using FRET. Japanese Laid-Open Patent Application No. 2005-207823 proposes a fluorescence spectral analysis method in which a fluorescence correlation analysis method or a fluorescence-intensity distribution analysis is performed based on received fluorescence using the FRET phenomenon.